Beta Distribution Parameters by Individual Group.

Beta distribution parameters for inter-big-attack sequences by individual terrorist group. Groups are rank-ordered according to their beta coefficient that represents the escalation in frequency of attacks prior to a big attack (defined as attacks resulting in 21 or more fatalities). The beta for fatalities represents the escalation in fatalities per attack prior to a big attack. The alphas represent de-escalation in frequency and fatalities following a big attack.